I'm writing the final filler article, and it occurred to me to have a section with ideas for filler arcs. Here's mine:
You didn't think the Fullbringer arc was as Chad-centric as promised? How's this for a Chad-centric arc? Ichigo and friends are forced to travel to a small village in Mexico to defeat a powerful Vasto Lorde from whom Chad's mother once narrowly escaped with her life (and then gave birth to Chad). The Vasto Lorde has invaded the human world and enslaved the population of the town as an experiment to create a soul farm so that he may ceaselessly feast without ever having to worry about the balance of souls, which ties in which Chad's past, since that's how his parents died. The Vasto Lorde's main purpose is to fill up with so many souls that she is able to create her own "negative" Hollow universes which she can selfishly control. Ichigo is overconfident, and the Vasto Lorde defeats Ichigo since its power is to rip out the Hollows from inside people like a dark vacuum; Chad is somewhat affected as well–but, much to the Vasto Lorde's shock, it's only given Chad new avenues through which to explore his power, like unblocking a chakra. Now it's the incapacitated Ichigo that needs Chad's help, and they fight back to back against the Vasto Lorde's legion of shinigami possessed by Hollows (if the Vasto Lorde sucks the Hollow back out of the shinigami, they go into shock and die). Ishida is needed to keep the other, smaller Hollows from crushing them in or returning to their master's body, and Orihime provides much needed support shielding everyone against Ceros from Gillians and Adjuchas. The Vasto Lorde, being by her nature especially heartless, laughs at the bonds between humans, which will surely seal their doom. Each of our heroes is assaulted by a possession Hollow that drills into their souls, inflicting immense trauma. This is especially horrifying to Ishida, who as a Quincy despises Hollows. In his soul-turmoil he nearly fires at his comrades in a haze of hatred against shinigami and Hollow abominations, but he masters himself, and tells the Vasto Lorde that no matter what his friends are, in the end they are all human. This inspires Chad to activate his pride as a human, his skin, the gift given to him by the mother he never met but brought him into this world. His Fullbring, a power the Vasto Lorde has no experience fighting against at all, causes the Hollows inside them all (now rendered unvacuumable) to writhe and inadvertently give them a boost in energy, allowing them all (including Orihime, since she knows true evil must be vanquished) to defeat the Vasto Lorde in tandem; they're sure to give Ichigo the final blow so that the Vasto Lorde may be purified, rounding out Ichigo's arc of settling into his powers and Chad and Ishida recognizing they should attempt to keep the world in balance more. In the end, Chad wonders if he'll ever see the soul of his Mom in SS now that the Vasto Lorde has been purified, and he wryly acknowledges that he might not even recognize her, but he can still feel her love alive in his skin, a la Harry Potter and (gag) Gaara but without the magic of it lol. NO GOTEI 13 INTERVENTION WHATSOEVER.
I want to add other people's ideas, too. Please, tell me what you'd like to see in a filler arc. I reserve the right to play with your ideas.